3-D Shrek knocks Iron Man off North American box office top spot

"Shrek Forever After," the first 3-D sequel for the lovable ogre, opened this weekend at the top of the North American box office, ending "Iron Man 2's" two-week reign, preliminary figures showed Saturday.

The fourth of the Mike Myers-voiced animated series raked in 71.3 million dollars, well short of the record 121.6 million dollar opening set by its previous installment, "Shrek the Third," according to data released by box office tracker Exhibitor Relations.

Higher-priced, 3-D theater tickets likely deterred some moviegoers, observers noted.

The superhero sequel "Iron Man 2" fell to second place with 26.6 million dollars, bringing its three-week total to 261.3 million.

In third place was "Robin Hood", director Ridley Scott's latest historical epic starring Russell Crowe as the famous English outlaw. The film took 18.7 million dollars, with a two-week total of 66.1 million.

The romantic drama "Letters to Juliet" opened took fourth place, with 9.1 million dollars, ahead of romantic comedy "Just Wright," with a duo of rapper-actors Queen Latifah and Common, at 4.2 million.

Saturday Night Live-inspired "MacGruber" opened at number six on the box office charts with 4.1 million dollars, followed by by "Date Night" with Tina Fey and Steve Carell with 2.8 million dollars.

Eighth place went to fright flick "A Nightmare on Elm Street" with 2.3 million dollars.

Trailing ninth and tenth place were "How to Train Your Dragon," which took in 1.9 million dollars, and Bollywood musical "Kites," about a dance-teacher who marries women to provide them with green cards, which opened with one million dollars.